Showing papers in "Comprehensive Reviews in Food Science and Food Safety in 2011"

Natural antioxidants: sources, compounds, mechanisms of action, and potential applications

Abstract: While use of synthetic antioxidants (such as butylated hydroxytoluene and butylated hydroxyanisole) to maintain the quality of ready-to-eat food products has become commonplace, consumer concern regarding their safety has motivated the food industry to seek natural alternatives. Phenolic antioxidants can inhibit free radical formation and/or interrupt propagation of autoxidation. Fat-soluble vitamin E (α-tocopherol) and water-soluble vitamin C (L-ascorbic acid) are both effective in the appropriate matrix. Plant extracts, generally used for their flavoring characteristics, often have strong H-donating activity thus making them extremely effective antioxidants. This antioxidant activity is most often due to phenolic acids (gallic, protocatechuic, caffeic, and rosmarinic acids), phenolic diterpenes (carnosol, carnosic acid, rosmanol, and rosmadial), flavonoids (quercetin, catechin, naringenin, and kaempferol), and volatile oils (eugenol, carvacrol, thymol, and menthol). Some plant pigments (anthocyanin and anthocyanidin) can chelate metals and donate H to oxygen radicals thus slowing oxidation via 2 mechanisms. Tea and extracts of grape seeds and skins contain catechins, epicatechins, phenolic acids, proanthocyanidins, and resveratrol, all of which contribute to their antioxidative activity. The objective of this article is to provide an overview of natural antioxidants, their mechanisms of action, and potential applications.

Xylooligosaccharides (XOS) as an Emerging Prebiotic: Microbial Synthesis, Utilization, Structural Characterization, Bioactive Properties, and Applications

Abstract: Xylooligosaccharides (XOS) have great prebiotic potential and can be incorporated into many food products. XOS seem to exert their nutritional benefits in various animal species, which by definition have an intestinal tract populated by a complex, bacterial intestinal ecosystem. The production of XOS on an industrial scale is carried out from lignocellulosic materials (LCMs) rich in xylan by chemical and enzymatic methods and the latter is preferred in the food industry because of the lack of undesirable side reactions and products. The information available does not provide an exact explanation about the bioactive effects of XOS. Their fermentation results in the acidification of the colonic contents and the formation of short chain fatty acids that serve as fuels in different tissues and may play a role in the regulation of cellular processes. Only data from small trials are currently available to support use of XOS in the treatment of different clinical scenarios. Numerous questions about the molecular mechanisms of action or clinical indications of XOS and other prebiotics remain unanswered. This article presents XOS as an emerging prebiotic with more emphasis on its microbial production, structural characterization, and bioactive properties.

Factors Influencing Gel Formation by Myofibrillar Proteins in Muscle Foods

Abstract: Considerable research has been done to better understand the basis for gel formation by myofibrillar proteins (MPs) in effort to manufacture acceptable processed meats with lower cost and more desirable nutritional characteristics. Results from research available indicate that there is no substitute for the myofibrillar protein myosin in gel formation by proteins from a wide variety of animal and fish species. This report consolidates information on determinants of protein gel formation, examining types of muscles and fibers, the species influence, and interactions of the MPs actin and myosin with each other and with fat, gelatin, starch, hydrocolloids, some protein soy, whey, and nonprotein additives such as phosphates and acidifiers, and the influences of pH, ionic strength, rates of heating, and its absence, protein oxidation, as well as the use of transglutaminase and high hydrostatic pressure. It is of interest that myosin alone will form acceptable gels. Gel formation by MPs is optimized at pH 6, an ionic strength of 0.6 M, and at 60 to 70 °C. The observations that collagen-derived gelatin can reduce the rubbery texture of low-fat products and that solubilization of MPs is not always essential for gel formation, and the observation that good gels can be formed in the absence of salt, are exciting developments that should be considered as pressure mounts to continue to reduce fat and salt in the diet.

Nutritional Value and Technological Suitability of Milk from Various Animal Species Used for Dairy Production

Abstract: The analysis of nutritional value and selected traits of technological suitability of milk was performed on the basis of the available literature. This analysis concerned various animal species used for dairy purposes (cattle, buffalo, goats, sheep, camels, donkeys, and horses). It has been stated that a considerable diversity exists in the analyzed parameters and traits of milk, which results in various directions of milk utilization. Cow milk accounts for more than 80% of world milk production. It is the most universal raw material for processing, which is reflected in the broadest spectrum of manufactured products. Sheep and buffalo milk, regarding their high content of protein, including casein, and fat, make a very good raw material for processing, especially cheesemaking. Donkey and horse milk have the most comparable protein composition to human milk (low content of casein, lack of αs1-casein fraction and β-lactoglobulin, and high content of lysozyme). Donkey milk is additionally characterized by a fatty acid profile distinctive from milk of other analyzed animal species. Camel milk also has valuable nutritional properties as it contains a high proportion of antibacterial substances and 30 times higher concentration of vitamin C in comparison to cow milk. The composition of goat milk allows using it as the raw material for dairy processing and also to some extent as a therapeutical product (low content or lack of αs1-casein).

Factors That Affect the Content of Heterocyclic Aromatic Amines in Foods

Abstract: This review compiles the contents of heterocyclic aromatic amines (HAAs) in foods and beverages, collected from literature data along the period from 1992 up to 2009. Also, it describes the factors that affect the formation of HAAs in foods, such as the cooking method, including temperature, time, and frequency of turning of meat, during cooking. Other factors depending on the type of food and the recipe followed are pH, amounts of HAA precursors, types of amino acids, presence of certain divalent ions, and content of substances with enhancing or inhibiting effects on the formation of HAAs. In addition, there are other factors, which depend on the type of food, such as muscle tissue and the presence of certain genes, since the RN− allele in pigs increases the glycogen content of muscle. The dispersion of the bibliographic data is evident, and there are scarce data, even no data, referred to individual HAAs. Considering that the diverging results can be due to several causes, possible recommendations are given in order to prevent the dispersion of the results and to achieve more valuable information, applied to determine the HAAs exposure. Although there are not direct indications that HAAs represent a serious health risk to the population, and common cancers are produced by many factors including xenobiotics, all measures to minimize the formation of HAAs should be foreseen, some of which are indicated.

Scientific and Technical Aspects of Yogurt Aroma and Taste: A Review

Abstract: Yogurt is a basic dairy product that has been consumed for centuries as a part of the diet, even when its beneficial effects were neither fully known nor scientifically proven. With time, yogurt has been continuously modified to obtain a product with better appeal and nutritional effects. The flavor components of yogurt are affected because of these modifications. The present review article is focused on the influence of the different parameters and modifications on aroma and taste components of yogurt. Extensive work has been done to explore the effect of chemical components as well as the microbial, processing, and storage aspects. The popularity of yogurt as a food component depends mainly on its sensory characteristics, of which aroma and taste are most important. This review also outlines the effects of the different modifications attempted in the composition of yogurt.

Nutritional Properties of Bamboo Shoots: Potential and Prospects for Utilization as a Health Food

Abstract: Bamboo is intricately associated with humans from times immemorial. Popularly known for their industrial uses, a lesser known fact of bamboos is the usage of its young shoots as a food that can be consumed fresh, fermented, or canned. The juvenile shoots are not only delicious but are rich in nutrient components, mainly proteins, carbohydrates, minerals, and fiber and are low in fat and sugars. In addition, they contain phytosterols and a high amount of fiber that can be labeled as nutraceuticals or natural medicines that are attracting the attention of health advocates and scientists alike. The shoots are free from residual toxicity and grow without the application of fertilizers. Modern research has revealed that bamboo shoots have a number of health benefits: improving appetite and digestion, weight loss, and curing cardiovascular diseases and cancer. The shoots are reported to have anticancer, antibacterial, and antiviral activity. Shoots have antioxidant capacity due to the presence of phenolic compounds. The increasing trends of health consciousness among consumers have stimulated the field of functional foods and bamboo shoots can be one of them. Bamboo fiber is now a common ingredient in breakfast cereals, fruit juices, bakery and meat products, sauces, shredded cheeses, cookies, pastas, snacks, frozen desserts, and many other food products. This review emphasizes the health benefits of bamboo shoots and their potential for utilization as a health food.

Sourdough Technology—A Traditional Way for Wholesome Foods: A Review

Abstract: In the present era, consumers wish to have a wide range of foods that are nutritious and flavorful and have long shelf life without added preservatives. Sourdough is an important modern fermentation of cereal flours and water based upon an earlier spontaneous process. The sourdough microflora is dominated by lactic acid bacteria and, along with yeast, they play a key role in the fermentation of bread dough. Factors that affect the quality of sourdough are dough yield, temperature, type of starter culture, acidity of the medium, and the substrate. Sourdough is classified into 3 types (Types I, II, and III); the most widely used for commercial production is Type III. The sourdough fermentation has a number of beneficial effects that include prolonged shelf life, accelerated volume gain, delayed staling, improved bread flavor, and good nutritional value. Sourdough also improves sensory characteristics such as loaf volume, evenness of baking, color, aroma, taste, and texture of breads. Sourdough has been reported to contribute to extended shelf life by inhibiting spoilage bacteria and mold growth.

Phytosanitary Applications of Irradiation

Abstract: Phytosanitary treatments are used to disinfest agricultural commodities of quarantine pests so that the com- modities can be shipped out of quarantined areas. Ionizing irradiation is a promising phytosanitary treatment that is increasing in use worldwide. Almost 19000 metric tons of sweet potatoes and several fruits plus a small amount of curry leaf are irradiated each year in 6 countries, including the United States, to control a number of plant quarantine pests. Advantages over other treatments include tolerance by most fresh commodities, ability to treat in the final packaging and in pallet loads, and absence of pesticide residues. Disadvantages include lack of acceptance by the organic food industries and logistical bottlenecks resulting from current limited availability of the technology. A regulatory disadvantage is lack of an independent verification of treatment efficacy because pests may be found alive during commodity inspection, although they will not complete development or reproduce. For phytosanitary treatments besides irradiation, the pests die shortly after the treatment is concluded. This disadvantage does not hamper its use by industry, but rather makes the treatment more difficult to develop and regulate. Challenges to increase the use of phytosanitary irradiation (PI) are cost, because commercial use has not yet reached an optimum economy of scale, lack of facilities, because of their cost and current inability to feasibly locate them in packing facilities, lack of approved treatments for some quarantine pests, and concern about the process by key decision makers, such as packers, shippers, and retailers. Methods for overcoming these challenges are discussed.

Blueberries and Their Anthocyanins: Factors Affecting Biosynthesis and Properties

Abstract: Blueberry is one of the most popular fruits in North America and rich in anthocyanins. Its content in anthocyanins contributes to the health-beneficial effects of blueberry against several chronic diseases including cardiovascular disorders, neurodegenerative diseases, diabetes, and cancer. This paper summarizes various facts presenting blueberry as a fruit with huge potential for increased future consumption as a health-enhancing food. Factors affecting the biosynthesis of the various anthocyanins in blueberries, including agronomic and genetic factors, and the possible pathways of biosynthesis of the major anthocyanins present in this plant are discussed. The important health-beneficial effects associated with blueberry anthocyanins, properties of these anthocyanins leading to the beneficial effects, and food processing parameters leading to the depletion of the amounts of anthocyanins present in the final processed products are also briefly discussed. Furthermore, the general methods of extraction and analyses that have been reported for being successfully applied to blueberry anthocyanins are also reviewed. Practical Application: Blueberries are well known for their nutritional and beneficial health effects, however, information concerning the physiology behind the blueberry beneficial effects is still lacking. There is little or no information on the characterization of growing conditions on anthocyanins in blueberries and research is lagging behind on advanced methods of extracting blueberry anthocyanins.

Bacterial Quorum Sensing and Food Industry

Abstract: Food spoilage and biofilm formation by food-related bacteria are significant problems in the food industry. Even with the application of modern-day food preservative techniques, excessive amounts of food are lost due to microbial spoilage. A number of studies have indicated that quorum sensing plays a major role in food spoilage, biofilm formation, and food-related pathogenesis. Understanding bacterial quorum-sensing signaling systems can help in controlling the growth of undesirable food-related bacteria. This review focusses on the various signaling molecules produced by Gram-negative and Gram-positive bacteria and the mechanism of their quorum-sensing systems, types of signaling molecules that have been detected in different food systems using biosensors, the role of signaling molecules in biofilm formation, and significance of biofilms in the food industry. As quorum-sensing signaling molecules are implicated in food spoilage, based on these molecules potential, quorum-sensing inhibitors/antagonists can be developed to be used as novel food preservatives for maintaining food integrity and enhancing food safety. Practical Application: Bacteria use signaling molecules for inter- and intracellular communication. This phenomenon of bacterial cell-to-cell communication is known as quorum sensing. Quorum-sensing signals are implicated in bacterial pathogenicity and food spoilage. Therefore, blocking the quorum-sensing signaling molecules in food-related bacteria may possibly prevent quorum-sensing-regulated phenotypes responsible for food spoilage. Quorum-sensing inhibitors/antagonists could be used as food preservatives to enhance the shelf life and also increase food safety.

Evaluating Sweet Potato as an Intervention Food to Prevent Vitamin A Deficiency

Abstract: Vitamin A (VA) deficiency causes over 600000 deaths per year, mostly of young children or pregnant women. Populations prone to VA deficiency obtain about 82% of their VA from plant sources that are rich in pro-VA carotenoids such as beta-carotene. Orange-fleshed sweet potatoes (OFSP) are an especially good source. We evaluated OFSP carotenoid concentrations, bioaccessibility, and cooking and storage, then used this to estimate the amount of OFSP needed to supply 100% of VA for people at risk for deficiency. The grams/day of OFSP needed to meet VA requirements varies with age and sex, and with the amount of beta-carotene in the OFSP. Amounts ranged from 6 to 33 g/d (0.02 to 0.13 cups/d) for a 3-y-old child with marginal VA status; to 68 to 381 g/d, (0.27 to 1.49 cups/d) for a lactating woman with good status. These are amounts that can be eaten on a daily basis. The amount of OFSP needed to supply the VA requirement to all of the 208.1 million people most in danger of VA deficiency for 1 y is 2.1 to 11.7 million metric tons, or 2% to 11% of current world sweet potato production. The most important factor influencing the effectiveness of sweet potato for preventing VA deficiency, by far, is the variety of sweet potato used. Fat in the diet is also important. We conclude that OFSP could prevent VA deficiency in many food-deficit countries—if OFSP were substituted for white, cream, yellow, or purple sweet potatoes.

UHT Milk Processing and Effect of Plasmin Activity on Shelf Life: A Review

Abstract: The demand for ultra-high-temperature (UHT) processed and aseptically packaged milk is increasing worldwide. A rise of 47% from 187 billion in 2008 to 265 billon in 2013 in pack numbers is expected. Selection of UHT and aseptic packaging systems reflect customer preferences and the processes are designed to ensure commercial sterility and acceptable sensory attributes throughout shelf life. Advantages of UHT processing include extended shelf life, lower energy costs, and the elimination of required refrigeration during storage and distribution. Desirable changes taking place during UHT processing of milk such as destruction of microorganisms and inactivation of enzymes occur, while undesirable effects such as browning, loss of nutrients, sedimentation, fat separation, cooked flavor also take place. Gelation of UHT milk during storage (age gelation) is a major factor limiting its shelf life. Significant factors that influence the onset of gelation include the nature of the heat treatment, proteolysis during storage, milk composition and quality, seasonal milk production factors, and storage temperature. This review is focused on the types of age gelation and the effect of plasmin activity on enzymatic gelation in UHT milk during a prolonged storage period. Measuring enzyme activity is a major concern to commercial producers, and many techniques, such as enzyme-linked immunosorbent assay, spectrophotometery, high-performance liquid chromatography, and so on, are available. Extension of shelf life of UHT milk can be achieved by deactivation of enzymes, by deploying low-temperature inactivation at 55 °C for 60 min, innovative steam injection heating, membrane processing, and high-pressure treatments.

Cholesterol Content and Methods for Cholesterol Determination in Meat and Poultry

Abstract: Available data for cholesterol content of beef, pork, poultry, and processed meat products were reported. Although the cholesterol concentration in meat and poultry can be influenced by various factors, effects of animal species, muscle fiber type, and muscle fat content are focused on in this review. Oxidative red muscles tend to have greater total lipid and cholesterol contents, although differences in the same types of muscles or cuts have been reported. Moreover, contradictory results among various studies suggest that unless there are pronounced changes in muscle structure and composition, cholesterol content is unlikely to be affected. Second, multiple issues in cholesterol analysis, including sample preparation, detection, and quantification, were evaluated. Cholesterol content of meat and poultry has been determined mostly by colorimetry and chromatography, although the latter has become predominant because of technological advances and method performance. Direct saponification has been the preferred method for hydrolyzing samples because of cost- and time-effectiveness. The extraction solvent varies, but toluene seems to provide sufficient recovery in a single extraction, although the possible formation of an emulsion associated with using toluene requires experience in postsaponification manipulation. The most commonly used internal standard is 5α-cholestane, although its behavior is not identical to that of cholesterol. Cholesterol can be analyzed routinely by gas chromatography (GC)-flame ionization detector without derivatization; however, other methods, especially high-performance liquid chromatography (HPLC) coupled with different detectors, can also be used. For research purposes, HPLC-ultraviolet/Visible/photodiode array detector with nondestructiveness is preferred, especially when cholesterol must be separated from other coexisting compounds such as tocopherols. More advanced methods, such as GC/HPLC-isotope dilution/mass spectrometry, are primarily used for quality control purposes.

Phase/State Transitions of Confectionery Sweeteners: Thermodynamic and Kinetic Aspects

Abstract: It has been said that the key to making high-quality candy is understanding and controlling the transitions of sugar. Whether found as crystal, glass, or fluid solution, sugars impart the texture necessary to distinguish one confection from another and to provide a unique experience to the consumer. In principle, the phase/state transitions of sugars are best understood through careful application of the phase diagram. However, many, if not all, confections are not at equilibrium, meaning that the phase diagram is simply a starting point for understanding and controlling the state of sugars. An understanding of the thermodynamic driving forces that push a confection towards equilibrium and the kinetic constraints that control the rate of approaching that equilibrium are key elements to creating products with the desired texture, quality, and shelf life. In this review, we summarize the thermodynamic and kinetic aspects of controlling phase/state transitions in sweeteners, with particular emphasis on applications to confectionery products.

The Tuna Fishing Industry: A New Outlook on Fish Protein Hydrolysates

Abstract: Tuna (Thunnus spp.) and tuna-like species are significant sources of food and thus play a very important rolein the economy of many countries. More than 48 species of tuna swarm the Atlantic, Indian, and Pacific Oceans, and theMediterranean Sea. The annual global production of tuna has undergone a marked increase from less than 0.6 millionmetric tons in 1950 to almost 4.5 million metric tons in 2007. Tuna generally is processed as raw fish flesh and marketedas loins/steaks or as a canned food. In the tuna canning process, only about one-third of the whole fish is used. Thus, thecanning industry generates as much as 70% solid wastes from original fish materials. This waste consists of muscle (afterloins are taken), viscera, gills, dark flesh/muscle, head, bone, and skin. Conventionally, these protein-rich by-productsfrom the tuna industry are processed into low market value products, such as fish meal and fertilizer. However, a promisingalternative use of these by-products is as functional food ingredients. Fish protein hydrolysate (FPH), which is obtainedthrough hydrolysis of tuna waste, can be used as an ingredient in food industries to provide functional effects such aswhipping, gelling, and texturing properties. Recently, FPH was found to be a potential source of antioxidants (such aspeptides with anticancer properties), antianemia compounds, and components for use in microbial growth media. Thisarticle is intended to summarize the existing knowledge about FPH, highlight some pertinent information related to thetuna fishing industry, and provide a new outlook on the production and applications of FPH.

Navigating the U.S. Food Additive Regulatory Program

Abstract: The Food Additives Amendment of 1958 is the foundation for the US food additive regulatory program, which oversees most substances added to food This article is a comprehensive review of the program, including original analysis of pre- and postmarket safety standards for various categories and subcategories of substances and their uses; assigning the more than 10000 substances currently allowed in human food to those categories; and analyzing the US Food and Drug Administration's (FDA) review of more than 1900 petitions and notifications received from 1990 to 2010 Overall, federal agencies made approximately 40% of the 6000 safety decisions allowing substances in human food These decisions allowed an estimated 66% of the substances currently believed to be used in food Manufacturers and a trade association made the remaining decisions without FDA review by concluding that the substances were generally recognized as safe (GRAS) Robust premarket safety decisions are critical since FDA has limited resources to monitor potentially significant scientific developments and changing uses of a substance after it enters commerce and only has access to published data or data submitted to it In the late 1990s, FDA moved from promulgating rules for its decisions for food contact and GRAS substances to reviewing manufacturer safety decisions and posting the results of the review on the agency's website This shift appears to have encouraged manufacturers to submit their decisions to FDA for review but has limited public opportunity to provide input

Enhancing FDA's Evaluation of Science to Ensure Chemicals Added to Human Food Are Safe: Workshop Proceedings

Abstract: Science and expert judgment are the foundation for safety assessments of chemicals added to food to ensure their use is safe. Hazard characterization is the first step in a safety assessment. Advances in science and technology pose challenges to the regulatory system and raise questions about whether the current hazard identification and characterization process is able to systematically and transparently encompass such advances while remaining defensible. An April 2011 workshop sponsored by The Pew Charitable Trusts, the Institute of Food Technologists, and the journal Nature brought together over 80 experts in science and food policy from government, industry, academia, and public interest organizations to examine the principles underlying the development and use of scientific evidence needed for chemical hazard characterization. Participants discussed challenges of identifying adverse health effects, advances in science, uses of new screening technologies and human biomonitoring data, updating of study designs, and development and review of toxicity test guidelines. Brainstorming sessions allowed participants to propose alternatives to enhance FDA's evaluation of science for safety assessment. Although there was no intention to reach a consensus, several themes emerged including the need for clear procedures to develop validated toxicity tests; importance of regularly updating guidance documents relied upon by regulators and industry; benefits of transparency and public access to information; potential for greater interagency collaboration; opportunities to improve hypothesis-based research to make it more useful to regulatory decision making; and importance of staying abreast of scientific developments to ensure that safety assessments are made using sensitive and relevant methods.

Food Safety Challenges within North American Free Trade Agreement (NAFTA) Partners

Abstract: Organizational elements and limitations influencing the effective operation of the food safety regulatory infrastructures in the United States, Canada, and Mexico are compared. Progress to improve the safety of food in North American countries is hampered by common problems, yet differences exist. Foodborne illness surveillance and reporting are most comprehensive in the United States, but it is uniformly more reactive than proactive in all 3 countries. Food safety policy is based on outbreak data, but that may be short-sighted because these represent roughly 10% of foodborne illness cases. Food inspection in each country is done at 2 tiers (federal and other) by many agencies at 3 (federal/state-provincial/municipal) levels. Interagency collaboration at times of crisis is weak and frequent heterogeneity in training, inspection targets, and inspection rigor affect regulatory credibility. Enhanced recognition that industry has the prime responsibility for food safety is warranted (and must not be confused with self-inspection) along with justifiably aggressive regulatory agency interrogation of food safety system performance. End product testing should be used to verify safety system operation and should not be used to predict product safety. Specific microbial and nonmicrobial challenges to safe food in North America are highlighted and a rationalization of fiscal/human resource allocation to most effectively reduce the burden of foodborne illness is provided.

A Free Software for Food Industries to Ensure Food Safety: CARVER + Shock

Abstract: Bio-terrorism is not a new term for scientists. Post 9/11 the United States of America, as well as other countries which have grown well economically and countries undergoing the metamorphosis to developed nations, are under serious threat of bio-terrorism. This has led to the development of the software CARVER + Shock by Sandia National Laboratories and Food and Drug Administration (FDA), specifically for risk assessment and protection mechanism in the entire food supply chain from farm to table. This software requires training on the software front and interaction with industry people to chalk out a plan to safeguard the premises and the supply chain of the food products in the industry manufacturing. Such efforts should be well highlighted and advertised among food processing professionals, educators, students, and those government agencies concerning the food safety issues. Everyone must look at this software as this is going to be the future of food processing safety. This system works like Hazard Analysis and Critical Control Points and can be integrated for total quality management of the concerned industry. Our study has highlighted the application of this software in various food industries showing its strength and weaknesses.